Expansion boring-tool.



PATBNTED OCT. 24, 1905.

E. E. DAVIS. EXPANSION BORING TOOL.

2 SHBETS-SHEBT 1.

c/ flaiw Wit W V WV v Q 17w]? Tm eff] I WW APPLIUATION FILED AUG. 10,1903.

PATENTED OUT. 24, 1905.

E. E. DAVE.

2 SHEETS-SHEET 2-- UNITED STATES EMERY E. DAVIS, OF ST. LOUIS, MISSOURI.

EXPANSION BORING-"TOOL.

Specification of Letters Patent.

Patented Oct. 24:, 1905.

Application filed August 10, 1903. Serial No. 168,917.

To all whom it may concern.-

Be it known that I, EMERY E. DAVIS, a citizen of the United States, residing in the city of St. Louis, State of Missouri, have invented certain new and useful Improvements in Expansion Boring-Tools, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

My invention relates to a boring-tool pro vided with adjustable cutters and novel means for adjusting said cutters to accomplish the boring or reaming of holes of different sizes.

The invention. consists in features of novelty hereinafter fully described, and pointed out in the claims.

Figure I is a longitudinal section of my boring-tool. Fig. II is a longitudinal section taken on line II II, Fig. I. Fig. III is a cross-section taken on line III III, Fig. I. Fig. IV is a longitudinal section taken through the boring-tool on line IV IV, Fig. III. Fig. V is a perspective view of the wedge by which the cutters are separated and forced outwardly. Fig. VI is a perspective view of the Wedge-guide. Fig. VII is a perspective view of the two telescoping bushings on which the cutter-separating wedge operates. Fig. VIII is a perspective view of one of the split sections positioned in the cutter-separating wedge. Fig. IX is an inside face view of the nut-section shown in Fig. VIII. Fig. X is a perspective view of the nut by which the cutter separating wedge is actuated.

1 designates the bar of my tool, which is slotted transversely, as seen as 2 2, Fig. III. The slots in the bar receive the cutters 3, that are reciprocatingly positioned therein. The cutters have beveled inner ends, which are recessed to receive parts to be hereinafter described.

4 designates a slide-gib that is positioned in the bar 1 to bear against the forward edges of the cutters 3 and is confined in such position by a retaining-ring 5, fitted to the bar 1. Seated in the gib 4 are auxiliary wear-gibs 6, that rest immediately against the cutters and are held to the slide-gib by pins 7. (See Fig. II.) The slide-gib is carried to the cutters by an adjustment-screw 8, that passes through the end of the bar 1 and bears against the slide-gib to force it and the auxiliary wear-gibs to the cutters for the purpose of clamping them in the bar after they have been adjusted outwardly to the desired extent by the mechanism to be hereinafter described. Extending transversely into the bar 1 of the tool from one of its sides is a pocket 9, that terminates short of the opposite side of the tool. In the base of this pocket is seated a slotted wedgeguide 10, the arms 11 of which project forwardly toward the mouth of the pocket and against which bear the rear sides of the cutters 3. (See Fig. III.)

12 designates a master-bushing seated in the outer end of the pocket 9 and preferably having screw-threaded connection with the bar 1, as seen in Figs. I and III. This bushing is adapted to bear against the cutters 3 at its inner end and at its outer end is provided with an inwardly-extending annular flange 13, that bears interior stepped shoulders 14 and 15. The master-bushing is provided with sockets 16 to receive the engagement of a spanner by which the bushing is turned into the toolbar.

17 designates a cutter separating or spreading wedge that is loosely seated in the master-bushing 12 for longitudinal movement in the pocket 9. This wedge consists of a circular head 18 and a tapering tail 19, the latter of which bears at its point a circular sleeve 20. The wedge is made hollow for the reception of parts, to be subsequently described, and within its head 18 is an annular groove 21. (See Figs. III and V.) The sleeve 20 of the wedge occupies a position between the inner ends of the cutters 3, projecting through the recess therein when the cutters are in unspre'ad condition, and the sleeve is adapted to travel into the wedge-guide 10 to permit bearing of the tapering tail of the wedge against the inner beveled ends of the cutters to spread them when the parts are actuated in the manner to be hereinafter described.

22 designates the rear member of a telescoping bushing provided with longitudinal slots 23 and having a shank 24, extending rearwardly from its head 25, which shank passes through the circular sleeve 20 and bears against a short adjusting-screw 26, which passes through the bar 1 and the center of the head of the wedge guide 10.

27 is the forward telescoping bushing member that seats in the rear member 22 and is provided with slots corresponding to the slots 23 in said rear member. The

member 27 has a head 29 at its front end, that contains a wrench-socket 30, extending therethrough. The forward bushing member rests against the flanged shoulder of the master-bushing 12.

32 designates a shift-screw, the forward end of which is loosely seated in the head of the bushing member 27, and the rear end of v which is provided with a stud 33, that turns loosely in the forward end of the rear bushing-shank 24. In the forward end of the shift-screw is a wrench-socket 34, that is smaller than the socket in the bushing member 27, so that a wrench may be inserted through said last-named socket for the actuation of the shift-screw Without affecting said bushing.

35 designates a shift -nut operatively mounted on the shift-screw 32. (See Figs. I, III, IV and X.) This nut is provided with arms 36, that pass through the slots 23 and 28 in the telescoping bushing members 22 and 27 ,(see Figs. III and IV,) thereby placing the telescoping bushing in connection with said nut. Extending transversely of the arms 36 are fins 37.

38 are ring-sections rigidly mounted in the annular groove 21 in the head 18 of the wedge 17 and resting between the flanged shoulder 14: of the master-ring 12 and the flange 21 of said wedge. Each of these ringsections is provided with a diagonally-extending groove 39 in its inner face, (see Figs. VIII and IX,) in which the fins 37 of the shiftnut 35 operate.

In the practical use of my tool the operation is as follows: The adjustment-screw 8 is first loosened to relieve pressure against the cutters 3 by the gi-b 4i and auxiliary gibs 6, and the cutters are then shifted outwardly by the actuation of the following parts: Upon rotation of the shift-screw 32 it turns in the shift-nut 35, thereby carrying said shift-nut inwardly, and the nut being in turn in engagement with the ring-sections 38 the fins 37, which are seated in the diagonal grooves 39, move inwardly in said grooves until they reach the innermost ends of the grooves. Continued rotation of the shift screw causes inward travel of the shift-nut and ring-sections, and thereby carries the wedge 17 inwardly, so that its tail will move between the cutters 3 to a sufficient extent to spread said cutters into an expanded condi tion corresponding to the size of the hole to be bored. The cutters may then be secured by turning the adjustment-screw 8 inwardly against the gib l, and the tool is ready for use.

My tool is particularly useful in making two boring or reaming cuts, the first rough and the second a finished cut, and in this connection the parts are operated additionally as follows: W'hen the cutters have been spread to a degree corresponding to the size the hole is to be when finished, a wrench is introduced into the forward telescoping bushing member 27, and the telescoping bushing is thereby rotated in a reverse direction from the direction of rotation of the shiftscrew 32. By so doing the shiftnut 35 is rotated reversely by reason of its arms extending through the telescoping bushing, and the fins 37 on the shift-nut are turned in the diagonal grooves 39 of the ring-sections 38 to carry them to the forward ends of the diagonal grooves, thereby causing the ring-sections carrying the wedge 17 to be receded a slight distance. The cutters 3 are now moved inwardly toward one another until their inner ends engage against the tapered end 19 of the wedge, and the tool is now ready to make the first or rough out. To make the second or finishing cut and to spread the cutters into the desired position without measuring or calipering, it is only necessary to introduce a wrench into the socket 30 and rotate the same a sufficient distance to bring the fins 37 on the shift-nut 35, carried by the telescoping bushings, to the innermost ends of the grooves 39 in the ringsections 38. This movement causes said ring-sections, carrying the wedge 17, to move forwardly the same distance that they were previously receded, and the cutters are by this movement forced outwardly to allow the second or finishing cut of the proper diameter to be made. This operation of shifting the cutters to make the two different-sized cuts is accomplished quickly, and the tool does not have to be calipered every time a shift is made, as the operator need only move the shift-nut 35 to bring its fins from one end of the grooves 39 to the other, thus insuring the proper distance of travel in and out of the cutters 3.

I claim as my invention- 1. In a boring-tool, a bar having a transverse pocket and provided with a slot crosswise of said pocket, a pair of cutters positioned in said slot, means whereby said cutters are locked in position, a wedge operating in the ocket between the ends of the cutters, a gui e for said wedge, a screw rotatably mounted in said pocket and held from longitudinal movement for moving the wedge, a split ring fixed within the head of the wedge in which ring is formed a pair of diagonallyextending grooves, a shift-nut mounted upon the screw, and fins integral with said shiftnut that engage in the diagonal grooves of the split ring, substantially as specified.

2. In a boring-tool, a bar having a trans verse pocket and provided with a slot crosswise of said pocket, a pair of cutters positioned in said slot and having recessed beveled inner ends, means whereby said cutters are locked in position, a wedge operating in the pocket between the ends of the cutters, said wedge having a channel terminating in a sleeve projecting from the edge of the wedge through the recesses in the cutter ends,

a bifurcated guide for said wedge, the arms of said guide being adapted to receive the sleeve of the Wedge, a bushing projecting into the wedge-channel and comprising two telescopic members having registering longitudinal slots, a. shank extending from said bushing into the sleeve of the wedge, a screw journaled within said bushing and bearing against one of the bushing members, a shiftnut mounted upon said screw, said nut having arms workmg in said bushing-slots, fins on said shift-nut arms, and a split ring fixed Within the channel of the Wedge and having a pair of diagonally-extending grooves for engagement with said fins.

3. In a boring-tool, the combination of a bar having a pocket extending transversely thereinto and provided with longitudinallyextending cutter-receiving slots leading into the pocket, cutters located in said slots and having recessed beveled inner ends, a V- shaped hollow wedge situated in said pocket to operate transversely of the bar and directly against and transversely of the inner ends of said cutters, a hollow sleeve on the edge of said wedge and projecting through the recesses in the cutter ends, a slotted wedge-guide seated in said pocket and having arms bearing against the front sides of said cutters, said arms forming guideways for said wedge-sleeve, means for shifting said wedge to move said cutters outwardly, and means passing longitudinally through said wedge and said sleeve to direct the n1ovement of the wedge, substantially as set forth.

EMERY E. DAVIS. In presence of NELLIE V. ALEXANDER, BLANCI-IE HOGAN. 

